In this paper, a comparative study is done for different routing protocols in mobile ad-hoc network by using directional antenna. The directional antenna is metamaterial rectangular patch antenna. Performance of MANET (Mobile Ad hoc NETwork) can be improved using metamaterial antenna, because of directivity and compact size of metamaterial antenna. Complexity of routing is day-by-day increasing between mobile users because of dynamic nature of mobile nodes and rapid change in mobile topologies in MANET.